The SCOLE (NASA Spacecraft Control Laboratory Experiment) model is considered the best model for the coupled system consisting of a flexible beam with one end clamped and the other end linked to a rigid body. This model has been studied extensively, with most papers assuming that the flexible beam is uniform. In our study we allow the coefficients of the beam equation to vary with position, lik...

Finite element formulations based generally on classical beam theories such as Euler-Bernoulli or Timoshenko. Sometimes, these two formulations could be problematic expressed in terms of restrictions of Euler-Bernoulli beam theory, in case of thicker beams due to non-consideration of transverse shear; phenomenon that is known as shear locking characterized the Timoshenko beam theory, in case of...

We present a straightforward low cost liquid phase deposition method to coat arbitrary-shaped dielectric substrates with uniform electron beam sensitive polymer films. Furthermore, we investigate the use of electron beam lithography to pattern the coated pre-form substrates. The polymers studied are poly-methyl-methacrylate with different molecular weights, poly(methyl methacrylate-co-ethyl acr...

      Hydroxyapatite (HA) nano-rods with uniform morphology and controllable size have been successfully synthesized in the presence of cationic and non-ionic surfactants by a hydrothermal method. (NH4) 2HPO4 and Ca(NO 3)2.4H2O were used as the phosphorus and calcium sources, respectively. The composition of synthesized powders w...

Single-photon emission computed tomography (SPECT) is based on the measurement of radiation emitted by a radiotracer injected into the patient. Because of photoelectric absorption and Compton scatter, the γ photons are attenuated inside the body before arriving at the detector. A quantitative reconstruction must consider the attenuation, which is usually non-uniform. Novikov and Natterer had de...

among the intermolecular interactions, the casimir and van der waals forces are the most important forces that highly affect the behavior of nanostructures. this paper studies the effect of such forces on the adhesion of cantilever freestanding nanostructures. the nanostructures are made of a freestanding nano-beam which is suspended between two upper and lower conductive surfaces. the linear s...

in this study, nonlocal nonlinear instability and the vibration of a double carbon nanotube (cnt) system have been investigated. the visco-pasternak model is used to simulate the elastic medium between nanotubes, on which the effect of the spring, shear and damping of the elastic medium is considered. both of the cnts convey a viscose fluid and a uniform longitudinal magnetic field is applied t...

In this work, nonlocal vibration of double of carbon nanotubes (CNTs) system conveying fluid coupled by visco-Pasternak medium is carried out based on nonlocal elasticity theory where CNTs are placed in uniform temperature change and magnetic field. Considering Euler-Bernoulli beam (EBB) model and Knudsen number, the governing equations of motion are discretized and Ritz method is applied to ob...